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Water Stability vs. Water Quality
The Concept of Living Water


by Ben Plonski from LKP

     

Zen and the Art of Pond Ecology
 
Ponds are like people; no two are ever alike. Each one has a unique set of variables or characteristics which set them apart from others. Each one requires personal attention to be understood. Although each one desires to achieve a state of harmony or balance, each has a peculiar way of doing it. The individual expression which sets each apart is what keeps life interesting. It seems that people and ponds do have much in common. Maybe this is why we are so drawn to the pond. Most of us would agree, sitting by our pond after a busy day, brings a sense of peace. I think ponds help balance our lives. Achieving balance personally is important because it leads us to a sense of sanity or stability. However, achieving balance takes work, planning, persistence and time. Likewise, creating balance in our ponds means establishing a stable system and a consistent maintenance program which will run along smoothly without a lot of trouble. It means creating a basic stress free environment where the organisms involved are in harmony with one another. Creating pond stability is within the realm of preventive care. It is taking the long view on things and not just demanding instant results. It requires patience and persistence. Our goal is a pond in dynamic health; but health is not just the absence of disease, it is the presence of vitality. Health is a koi pond where the koi can actually grow and improve. Koi that live for a few decades rather than just a few years or months; koi that are not constantly weakened and threatened by infections. It's a water garden where the water plants are vibrant and flourishing and require frequent trimming. Algae is indeed present and part of these pictures. Bacteria is also properly cultivated and controlled, in the filter as well as in the water. Protozoans, worms, aerobic and anaerobic bacteria, pathogens, algae, plants and fish are in proper proportions.
They are in a state of dynamic equilibrium where the health of one organism is directly affected by the health of all others. This is what I call Living Water.

Defining Stability
The dictionary meaning of the word "stable", besides being a place to keep horses, describes "the ability to remain unchanged in form or character; and an ability to recover equilibrium after being slightly displaced; and, not readily decomposing or changing".

I for one have to admit to more than slightly displacing the stability of my ponds. We are usually the ones responsible for throwing our ponds out of whack. Then we expect instant results out of mother nature to bring it back. There is a truism in aquatics which states that "nothing good happens fast". When we want instant results, we do things which we later regret. But that doesn't seem to matter when our pond suddenly goes green right before we have a big party. Which reminds me of another truism which is" Ponds always turn green right before a big party". But that is another story.

Water stability is the prerequisite to balance. Stable water conditions promote good water quality. Stable pond conditions determine how long it will take for mother nature to reach a state of dynamic equilibrium. The microorganisms, plankton, algae and plants and fish depend on a stable water chemistry in order to function properly without constant disruption. Most organisms in the pond are quite capable of functioning outside of perfect preconceived notions. What they are not good at is change. Endless change within the water affects all organisms negatively, not just the fish. The fish depend on these multitude of organisms to condition the water. Constant change within the pond chemistry and environment creates antagonism. The good bugs are out of balance with the bad bugs. The fish are usually the ones to pay for this antagonistic environment.

What does water stability have to do with water quality?
As I mentioned, stable water conditions promote good water quality. A lot of what we call good water quality is created by the action of bacteria and microalgae decomposing the fish's waste products. These make up the interactive soup called Living Water. These microorganisms are inhibited by chemical and physical changes because they must adjust and this takes time. The organisms are not flourishing simply because all their energy is going into adapting. Thus, our fish are swimming in a soup where natural microbial balances are out of check. *Mind you, your test kit may read perfect water quality but the "Living Water Quality" is in a state of antagonism. We can say that the biological stability is upset. Biological stability keeps bad bugs in check.

Preconceived Notions
All too often we make changes to the pond to satisfy a preconceived notion of "good water quality" or to fix an algae problem or treat sick koi. In the process we can take a step backwards. Because in the very act of trying to make things right, we disrupt what is present. We disrupt the existing stability to satisfy a preconceived notion of what stability should be. Conditions in the pond may not be perfect, but the organisms within are already adjusting to it. Our changes for the better must not do more damage than good.

Water quality guidelines of which we are very familiar; ph, ammonia, nitrite, oxygen etc.
are given as an index, not as an absolute number. You will wear yourself and the fish out striving for perfect numbers. Daily observations and flexibility coupled with small careful changes often give faster results. The koi will tell you if there is a problem. I have seen many ponds where the water quality numbers were not good but the koi appeared happy. This does not mean that we should not strive for better numbers. It does mean we need to proceed with caution and gently make small corrections. It is up to us to provide the correct environmental conditions conducive to stability and at the same time give us desirable numbers.

This reminds me of a time when my breeder, Mr. Nagata, was in our shop with some very nice koi. I had tested the water and it registered fairly high nitrites. The koi actually looked quite fine but I did not want his fish to get sick. So I proceeded to make a very large water change of 50% to improve conditions. Mr. Nagata came in and saw what I was doing and yelled
"What are you doing?" "This is no good,"Very bad". Of course I responded that I was correcting the nitrite problem. He just shook his head in disbelief that I would make such a big water change. As it turns out, the koi were fine and a better course of action would have been to make a smaller water change and gently clean the filter. This would have supported the nitrifying bacteria and the Livinig Water Quality better than the big water change. As it turns out many nitrifying bacteria are in the water itself. A big water change can stunt the nitrifying bacteria and often simply prolong the nitrite problem. The large volume of new water is drastically different from the Living Water Complex. The large water change may indeed dilute the nitrite but it also dilutes the bacteria who must eat the nitrite. Further, since the new water is sterile, full of chloramines, a different pH, a different temperature and oxygen level it actually inhibits the remaining bacteria. The koi were in less distress with the nitrites than with my corrective actions.
Needless to say this started me thinking about my preconceived notions and about the concept of Living Water.

The Concept of Living Water
When we sit back and enjoy our ponds we focus on the obvious fish and plants. However, what we are really looking at is a tremendous soup of various organisms all
striving for a harmonious existence. We test the water and it checks out good. But what is really happening is a complex dynamic chain of interdependent relationships, from ions and molecules to microorganisms, plants and fish. Each ingredient plays a role in the individual characteristics of your pond. No two ponds are ever alike. When water is confined, it's components begin to reconfigure themselves, developing a unique condition and different from it's original state. Every water change or manipulation by us will affect the water chemistry and organisms, good or bad, depending on the degree of change. Every action we take or do not take has a consequence. You have heard it said that to be a successful koi keeper you must be a good water culturist. Or, "Take care of the water and the water will take care of the fish." I am sure you have also heard that "Clear water is not always healthy water". I would like to extend this idea to: "Water which tests good does not always have healthy koi". I often hear this complaint; "My koi are all sick but my water tests perfect".

Living Water is the caretaker of our fish. Living water is the bacterial and planktonic soup which supports our koi at the top of the food chain. Actually a tremendous part of the pond's biofilter are the organisms in the water itself. I have an old Nichi-Rin magazine which states that nitrifying bacteria are free floating in the water. The same article goes on to state that the
bacteria which colonize a "proper" filter system will condition the water in other ways like giving water clarity through phosphate removal, nitrate removal, carbon recycling, etc. The filter and the Living Water are in a continuous relationship where one affects the other. There are many types of bacteria in the pond which do other jobs besides just nitrification. This hobby seems to focus on the nitrifying bacteria with little regard for the tremendous populations of other very important bugs.

Remember the beer commercial, "It's the Water". Consider this, if your filter makes up 10% of your pond volume; that leaves 90% Living Water. I want to mention one of the ponds we have maintained for over 7 years. This pond has no biofilter and no U/V and gets 8 hours of sun per day. The filter consists of a sump with screen in it to extract solids. It is approx 3000 gals and holds 15 large koi. This pond is totally under filtered with no plants and yet tests zero ammonia and nitrites and yes the water is crystal clear.. The bacteria and algae in the water and on the walls of the pond are doing the job. Now this is where I say, "Don't try this at home folks.". This pond did not achieve this condition over night. It is over 15 years old and it does have a continuous 5% daily water change.

Probiotic Water
Happy, balanced, Living Water acts as a natural probiotic. Probiotic bacteria is nothing new. In nature it is called bio-diversity. Natural ponds have such a tremendous diversity of organisms that no one pathogenic organism can take over. It is only when we put our koi into crowded unstable conditions that they break down and the pathogens can take over. Living Water is the concept we are using when we add probiotic bacteria like Lymnozyme to prevent infection.

Algae
Quite often mother nature's idea of harmony or balance is nowhere near what we want. Mother Nature's answer to dynamic balance usually includes algae. Possibly, lot's of it. Algae is a wonderful organism of which we are deftly afraid. In fact, some people are such "algaephobes" that in the process of trying to eliminate algae from their pond they kill all their koi. "GUILTY!" . Planktonic algae is part of the Living Water complex, it has to be. Algae is just making up for excess nutrients. When the Living Water or the filter bacteria are not functioning, the algae flourishes. On the other hand, the end product of biofiltration is nitrate.
Algae is only completing the filtration process. Yes, it is possible to have a pond in full sun without any U/V sterilizer and have very little algae, sometimes it is easier said than done. Living Water is the concept we are using when we add bacteria and enzymes to a pond to control algae. Many factors are involved, including the age of the pond, the filter system, the pond husbandry, the fish load, aquatic plants and the Living Water Quality.
     Don't try to kill algae. Algae is inevitable and desirable. Learn to appreciate algae. It is making up for lack of filtration. In some ponds algae IS the filter. Algae grows due to excess nutrients, sunshine and lack of bio-competition. Minimize algae occurrence with proper filtration, aquatic plants and/or small frequent water changes. Use enzymes, barely straw, shade; non antagonistic methods. Use algaecides as a last resort. Ultraviolet sterilizers assist proper pond and filter designs. We are making the transition from sterile thinking to stable living thinking. We have seen that what we do to the water, we also do to the fish. Our goal is to achieve maximum water quality by controlling stability within the system. Now we will discuss correct techniques and pond systems which are conducive to stability and lead us to good Living Water Quality.

How do we establish and maintain water stability?
Each pond has individual characteristics which control it's ecological stability. A simple water garden is very different from a show quality koi pond. Most ponds fall somewhere between these two extremes. Creating stability means knowing the limits of your system. If you exceed the limits you will pay. Some of us only find our limits by exceeding them. "GUILTY!" You will get in trouble if you try to apply one pond philosophy to all ponds. Each pond will have to achieve stability in it's own way. The bottom line is to be flexible; understand the principles; develop your experience and adjust your decisions based on daily observations.

Be Patient.
I think time is one of the most important elements to achieving stability. Mother Nature just doesn't work fast. I think many ponds are not really well established until after 2 to 3 years of good management. Your water may be clear and your test kit may have good numbers within 3 to 6 months, but true ecological stability is more than this. It's no wonder so many people fail when they are starting out. We want an instant pond. We want a pond that looks like it is 5 years established and we want it NOW. Furthermore, we expect this from a poorly planned and designed system. Then we expect it to do things of which it is not capable.

Planning and Sticking to the Plan.
What do you want from your pond? A water garden; an ornamental pond with koi and plants; or a show koi pond. Each of these 3 "types" of ponds has a specific goal or desired environment. Each has specific requirements in order to achieve this goal. Each of these "types" of ponds also has certain limitations. When we exceed these limitations or deviate from our original goal we can expect problems.
You would not build a beautiful water garden with many delicate aquatic plants and then throw some koi into it. Even small koi will grow into big insatiable koi in a few years or even months. Would you make a pond as a large koi display and then throw in one water lily? Sure, if you like to waste money and clean up dirt. Likewise, you would not put a small filter on a koi display and expect it to strike a balance. Nor would you build a water garden and forget to add the proper number of oxygenating grasses.
If you leave the proper ingredients out of your intended system it will not function as intended and you will be faced with modifying the system to accommodate your new requirements. The trouble is, most of us do not know the limitations of our systems and we basically just WANT IT ALL. I think it is important for us to decide what type of system we want and then do the research and take the steps to achieve it.
All 3 of these types of ponds can be very successful when properly built and maintained. They can also fail quite disastrously when limitations are exceeded. They are successes or failures for the same common and basic reasons. We will now discuss some of the common ingredients

SIZE
Sheer volume of water is probably the single most important element to achieve water stability. Most ponds are too small. A large volume of water has greater dilution of wastes, is more temperature stable and the chemistry changes more slowly. Size does matter! Volume makes up for a lot of mistakes. Large ponds have healthier fish and less disease. Make your pond as big and as deep as you can the first time because I guarantee that you will always wish it was bigger after you are done building it. Always!

  • A water garden with only a few goldfish can be small and hold as little as 10 to 100 gallons. A water garden has better gas transfer when it is shallow, say 18" to 24" deep.


  • An ornamental pond with plants and koi should be 2 to 3 feet or deeper and incorporate shallow areas for plants. Size should be closer to 1000 gals or bigger.


  • A full fledged show quality koi pond would have few or no plants within the pond and be 4 feet plus in depth and averaging over 5000 gals.

Sun is a factor. A pond with lilies will require a lot of sunshine. Bog plants require less sun. Koi fish do not do well out in full sun and require shade from midday sun. Direct sun will heat your pond in the day and likely go cool at night. Shade gives temperature stability. You will have much better control of your algae if your koi pond is shaded.

 

POND SHAPE AND CIRCULATION
Simple pond shapes are more easily cleaned. Simple shapes with good water movement will not have stagnant areas. Oxygen is a major key ingredient to stability. Stable, Living Water depends on stable levels of oxygen 24 hours a day. Good circulation creates a homogenous mix of oxygenated water. Furthermore, good water movement facilitates collection of debris for removal and filtration. I think it is important to note that some pond designs require more circulation than others. Namely, these are the types of ponds which have gravel on the bottom of the pond. These systems have a higher circulation requirement to prevent debris from settling and to promote aerobic conditions within the gravel. Big pumps make gravel bottomed ponds work better. On the other hand, a water garden requires little movement because fish loads are very light and food going into the system is minimal or absent. Koi display ponds have central drains and self cleaning designs and may only require a gentle current with smaller pumps to circulate efficiently. The shape of the pond itself is focused on removal of wastes.

 

FILTER SYSTEMS
My favorite subject! This is the next item which is almost always too small. Again, size does matter! How do you expect to achieve stability with a biofilter that requires weekly cleaning?
When a biofilter is too small for the waste load of the pond you will be cleaning it too frequently. The good bacteria will be washed away too frequently.

Try these filter sizes:

  • A water garden filter gallons should be 2% to 5% the volume of the pond. 1% to 3% as media.

  • An ornamental koi/plant pond filter gallons should be 5% or greater depending on fish load. 3% as media.

  • A full fledged koi display pond filter gallons should be 10% to 20% the volume of the pond. 6% to 8% as media.

When you install a prefilter ahead of the biofilter you just made a quantum leap in achieving stable Living Water Quality. A good prefilter prevents solids from reaching the pump and biofilter. Now you can clean the prefilter without disturbing the biofilter bacteria. The biofilter bacteria are very slow growing and are easily lost in vigorous frequent cleaning. A good filter system would require weekly cleaning of a prefilter and cleaning the biofilter once or twice a year! This is the difference between filtration and water purefication. This is a very important concept to understand. Filtration is the removal of solids from the water. Purefication is the conditioning of the water by the action of bacteria, microorganisms, algae and plants. As the water flows through the biofilter, it is in contact with large numbers of bacteria. These bacteria not only consume ammonia and nitrite but recycle all the other dissolved organic and inorganic wastes like phosphates and carbon based molecules and left over small solids which past through the prefilter. These bacteria grow on and in between the media, layer upon layer in a bacterial matrix that becomes a little universe all it's own. This stable population of bugs requires good oxygen flow and stable conditions to flourish. These bugs may take 6 months to a year or more to fully establish. Frequent "disruptive cleaning" of the filter media washes away stable colonies of bacteria. Large filters will bounce back more easily than small ones. Ponds in very cold climates may rely on many aquatic plants for bilfiltration since the bacteria often freeze in the winter and a biofilter is restarted every year.

Gravel Bottoms
Ponds with gravel on the bottom do provide a tremendous surface area for Bio-filtration. However, heavy feeding of large koi populations along with poor circulation will build up overwhelming solids within the gravel. The bacteria can only digest so much. Sooner or later you will have to disturb this muck to remove the build-up.
This is when you have exceeded the limits of this system. Please remove your koi during this process. This "disruptive cleaning" affects stability. The pond will indeed readjust. The questions are; what effect will it have on your koi? What effect will it have on your algae balance? How long will it take to regain stability and balance? Time will set things straight with the algae. When done carefully your koi will readjust too. Worst case scenarios are sick or dead fish and algae blooms with a vengence.. These systems are fine if you keep fewer koi and your circulation prevents most of the debris from collecting in the gravel. Less than 3/4" deep of small 1/8" grain gravel will also prevent waste buildup. Small grain size and shallow gravel bottoms can be mouthed clean by koi. Do the math and you will see that this amount of gravel on the bottom is equal to 3% - 5% of the pond volume which is similar to what I recommended for media in an external filter. The difference is in how we prevent solids build-up. An external filter system with a good prefilter does not require disruptive cleaning. For better luck with gravel bottom ponds, keep your skimmer prefilters clean and provide excellent circulation to prevent solids from gathering on the bottom.

Some of the bacteria in the bio-filter and gravel bottoms consume high quantities of phosphorous. In fact, given stable conditions, some of these phosphate eating bacteria can actually grow faster than algae. They are capable of digesting enough phosphate that the algae just starves. This is how a pond clears itself of green water or hair algae when the system is given time and stability. Frequent "disruptive cleaning" of the BIO-filter or gravel bottom is antagonistic to stability. This is one reason why ponds go green after a vigorous filter cleaning. Improper filtration is also the reason ponds need big U/V sterilizers.
A proper filter size and design greatly reduces the need for a U/V.

Disruptive Cleaning and Disease.
Most fish ponds have a higher level of nitrogenous waste than would be found in nature. We keep too many koi and we feed very concentrated, protein rich koi pellets. This means that our filters and water tend to have a high count of proteolytic bacteria which consumes these wastes. These proteolytic bacteria are growing in very high concentrations in the biofilter or gravel bottom. These bugs do not belong in the pond water on the fish. When we disrupt a biofilter or clean a gravel bottom, we potentially release these proteolytic bacteria into the pond. They are more than happy to continue feeding on proteinaceous material, only this time it is your koi's skin. This is one good cause of ulcer problems. Many times I have seen koi in great shape until the biofilter was cleaned. This is another reason why a proper filter design is important. A good filter design cleans easily without excessive disruption. A good design lets go of the dirt with minimal impact to the bacteria. A good design does not release toxic filter by-products or proteolytic bacteria back onto the fish.

I remember a pond which looked very good and the koi were healthy. However, the gravel biofilter had not been deep cleaned for over one year. Furthermore, it had not been completely taken apart for over 5 years. This bio chamber had a good settling tank ahead of it but we still assumed it would be very dirty. We completely removed the gravel and to our surprise it was not dirty at all! The interesting part was after we "cleaned" it and turned the filter back on, all the koi huddled in the opposite corner as far away from the filter as possible for over one week. Fortunately, the koi remained healthy, but this does show that we released some very uncomfortable chemicals or bacteria which really bothered the koi. Had this filter been full of black anaerobic sludge, I cringe at the thought of what may have occured.

The Case for Multi-Chambered Filters.
In general, multichamber filter systems are more stable than a "one tank does it all" approach.. You can clean one of the chambers at a time and thereby not disturb the entire system. When you clean individual chambers you are less likely to flush loose waste and bad bacteria back onto the fish. Chambers toward the end of the system can literally stay clean. The bacteria in these systems can grow in peace and truly stabilize. Water quality produced by multi-chambered filters is the best. The best water quality is achieved when your filter is gravity fed and the pump is at the end of the system. I have said it a thousand times, "keep the solids out of your pump". You instantly pollute your water when the fish waste goes through the pump. This creates an endless list of potential problems including hole disease and algae problems. In my experience, the advantages of a large, gravity fed, multi-chambered, non-pressurized filter put them at the top of the list of choices available today.
A well designed multichambered filter can be highly successful with many different types of media including stone. Various filter media are available which are very easy to clean of dirt without dislodging much bacteria. Japanese mat in a honey comb configuration does not trap the dirt within the media. Suspended solids will have to be removed either through settling or other prefilter tank. This keeps the dirt out of the japanese mat and it remains aerobic. The new Matala filter mats are unique in that they can trap dirt but easily let go of the dirt without losing too much bacteria. The 4 various densities of Matala can be arranged sequentially so as to trap dirt in the prefilter section and function as a highly aerobic media in the biofilter section.
Note: Anytime you can settle debris, rather than trap it, you will improve filter performance.

Fish and Plants
Stocking the pond with plants and or fish is the next step to water stability. What is the first thing you can't wait to do when your pond is built? Get the Fish!! Yea! We are in a hurry to stock the pond. As most of you know stocking our ponds with koi is very challenging. New ponds should try to get some basic balance going before we add fish. We need some algae and some bacteria before the fish go in. If aquatic plants are to be used, add them ahead of the fish and give them a chance to establish themselves. Give the pond some time and add an over the counter bacterial product to give the pond a little jump start. You may also use the aged conditioned "Living Water" from a friend's healthy pond.

Add only one or two koi at a time whether your pond is new or well established. Build your fish population slowly. Give each new koi a chance to adjust, maybe one or two months. This gives all your established koi a chance to adjust slowly to the new guys too. Remember, your new koi is quite likely to be in a state of distress due to the shipping and handling process. His immune system is already compromised and he needs a stable new home environment. The easier you make this transition on him the better.

Know Your Source.
Before buying a koi ask your dealer what his water temperature is. What is his pH? Do his koi look healthy? When and with what did he medicate? Does his water smell fresh? Does he have a microscope and use it? How long has he had this koi? Was it mixed in with any new shipments? These are questions you should ask before you bag the fish. Good dealers work very hard to provide healthy koi but the reins are being handed over to you. You need to decide if this koi is really ready to go home to your pond and is your pond really ready for this koi.

Quarantine of new koi can either contribute to stability or disintegrate it. Most quarantine ponds are too small and under filtered. Improper quarantine is actually worse than just throwing new koi right in the pond. Your koi can come out of quarantine weaker and more susceptible to disease than when first purchased. Proper quarantine is a bonus when done in large tanks of greater than 300 gals. You can stabilize your new koi for one month or more and watch for signs of illness.
You must realize that every time you add koi to your existing population you are essentially disrupting stability. Along with the koi come their bugs. Strong and stable koi will have stable bugs, bugs which are in commune with the fish. Existing koi and new koi will have to share each others bugs. Often times, koi have to get sick to acquire new immunity. This is when all hell can break loose if your pond is overcrowded.

Overcrowding.
This factor is a critical ingredient to gaining or losing stability in the pond. It is directly related to pond volume and filter size. Every pond has a stocking limit. Once you have exceeded this limit you can expect problems. Everybody wants"just one more fish." Unfortunately, most of us will not know when to stop. Most hobbyists find that they don't have disease problems when they first start adding koi.because it is not overcrowded. Once the population reaches a critical level, parasites or bacterial infections start showing up. Of course it is always the dealers fault. In fact, it may very well be the dealers fault because he did not try to talk you out of buying too many koi. I find it interesting that a given pond will continue to somehow reduce it's population over and over again, despite our efforts to try and push the limits. We cannot expect to randomly throw in new koi from various sources without having a major pathogen outbreak. Natural pathogen/probiotic balances take time. Plus an individual system is only capable of handling limited quantities of waste before balance and stability is upset. I am constantly amazed at the quantities of food that koi require and the triple quantity of waste this seems to produce. Koi are not really fishthey are "Water Pigs".

Yes, it is possible to exceed the limits for awhile. Goldfish can live for 10 or more years and koi can live 25 years plus. So do we call ourselves successful when we can overcrowd our pond but the koi live only a few years? Are we constantly replacing koi to bring our population back up? Are we successful because we know how to give our koi antibiotic injections to prolong their overcrowded existence for another year or so? As a koi dealer I should probably just shut up now. However, as a koi dealer I do have a responsibility to the koi and the hobbyist. The fact remains, overcrowding kills koi and makes ponds look bad eventually. The fact also remains that you can keep many koi alive and well with above average water keeping skills, large proper filter systems and a good diet.

Try these stocking rates if you are having continuous disease problems.

Water Garden/Plant Ponds.
     Without filter:     Zero Koi.     One goldfish per 50 gallons.
     With filter:          Zero koi.      One to 2 goldfish per 50 gallons depending on filter.

     Ornamental Koi/Plant Ponds.
     Filter 5% volume of the pond; 3% as media:       One adult koi/300 gals.     1000 gals minimum.

     Koi Display Pond.
     Filter 10% volume of the pond; 6% as media:     One adult koi/200 gals.     2000 gals minimum.

     Show Quality Koi Display Pond.
     Filter 10% or greater; 6% or greater as media:     One adult koi/500 gals.     5000 gals minimum.

I can hear it now, "There is no way in hell that I am going to keep so few koi!"
"That's only 2 to 6 koi per 1000 gallons! " "Besides, I have a lot more koi than that right now and they are just fine." All I have to say is; "Make a bigger pond. Have you ever seen a 3 year old koi at 22"? How about a 5 year old at 28"? "Well yeah, but my koi are only like 6 inches long!" Imagine six cute 6 inch baby koi in 1000 gallons in 3 to 5 years from now. Plan for future growth. Koi need a lot of room. How many Chihuahua dogs would you try to contain in the same small space? Who am I kidding; 99% of hobbyists will not listen to this. I do know from experience that under stocking has never been problematic except for upsetting my insatiable desire to have more koi. Ponds which are not overcrowded simply do not have the incessant uncontrollable diseases present in today's koi mania hobby. Koi can actually fight infection and parasitic diseases without us declaring chemical warfare on the pond. Living Water Quality is very high and stable at low stocking levels.

Are some parasites desirable?
On the microscopic level, the bugs on a koi's skin and mucous is another universe all it's own. The skin and mucous are in a dynamic exchange with the Living Water around it. To say that a koi is at one with his surrounding water is an understatement. The chemicals in the water, the microorganisms, the fish's diet, all affect the koi's health. Pathogens are always present. We cannot eliminate parasites. We can minimize stress and maximize pond stability. Medications merely reduce pathogens long enough for the fish to regain stability. A mucous scraping of healthy koi will usually reveal some parasites. Some parasites, like trichodina, are commensal organisms living symbiotically on the mucous of the fish. They eat excess bacteria and organic debris. In a way they are like ants or spiders in a garden. Trying to sterilize the koi will do more damage than good. We wipe out the good bugs with the bad. A few of these bugs may indeed be desirable. Koi breeders in Japan and around the world understand that regardless of the parasite, it is the level of biological stability which determines a disease outbreak. So what will you do the next time you see your koi casually scratch himself on the walls of the pondPanic? Should you dump in every known chemical to eradicate the disease or should you seek clean stable water conditions? Should you question your maintenance techniques or filtration? Should you get rid of 50 or so extra koi?
Remember, when medication is inevitable, a stable pond will bring quicker results.

Medications Effect on Living Water.
Inevitably we do things which will disrupt stability and effect our Living Water Quality. Stability has been knocked out for whatever reason and due to overcrowded conditions we might have to medicate. First, we must gently encourage the pond back to stability before we consider medications. Reduce the stress and fix the water FIRST. Whatever you do, don't panic; panic pushes us to do regretful things.
Basically, ALL medicines are antagonistic to Living Water Stability.

Consider these points when medication is inevitable.
Know the gallons of your system.
Know what parasite if any you are dealing with.
Use a specific medicine for a specific bug.
Treat accurately and promptly.
Do Not Over Treat or Over Dose. You will kill the Living Water or the filter bacteria.
Formalin and potassium permanganate and salt are all over used in the industry. Use judiciously.
Change small quantities of water after treating to dilute toxins and improve water quality.
Sometimes it is better to medicate individual fish in a separate bath if practical. In this way you won't impact the Living Water.
Focus on stability. Are your actions contributing to stability or antagonism. All to often, we do TOO MUCH.

Maintenance
Establish a consistent maintenance program to promote stability and ease back pain. The design of the pond should revolve around ease of maintenance. If you set up your filter so it can be easily backwashed, you are more likely to do it religiously. What I see all too frequently is a pond which goes from one extreme to another, too dirty, too clean, too dirty, too clean. Letting the pond turn to garbage and then completely cleaning everything will never get you to the balanced pond you were hoping for. Alas, many pond and filter designs limit us to this kind of cleaning. Get the right filter design and you will be in charge.

Water Changes and Filter Cleaning.
Proper water changes are extremely valuable in maintaining stability. However, tap water is totally different from your ponds water in pH, alkalinity, temperature, salinity, dissolved oxygen, it is sterile and contains chloramines. Make small water changes frequently. 10% water changes spread out more frequently are better than big water changes done infrequently. Don't make big water changes unless absolutely necessary. Some emergency situations may indeed demand a large dilution. Toxic chemicals like pesticides or paint would require an immediate 70% to 100% water change to save the fish. A high ammonia or nitrite level would be better controlled with 10% to 20% daily water changes and corrective filtration principles.

In Japan the dealers provide a continuous drip or small stream of new water into the pond at all times. The pond continuously overflows via an overflow pipe. This drip may constitute a 5% to 10% daily water change. This, over time, establishes a very clean and yet stable water condition. Of course they are using well water. In other parts of the world we have too much clorine or cloramine to make this a feasible option. However, we can add up to 2% or 3% daily without dechorinating and without any harmful effect. In fact, I know of a few ponds here in So. California using this approach with great success and nitrate readings as low as 20ppm with heavy fish loads. You will need an adequate overflow pipe to accomplish this successfully.
If you cannot use the drip approach you will simply have to change water when you backwash your filter. Crowded koi ponds or show koi displays may need 25% to 65% or more, monthly water changes. Be careful of chloramine. Water gardens do not require large monthly water changes.

Don't mess with the pH too much.
Fixing "too high" or "too low" a pH can kill fish. Understand your reason for improper pH balance. Do not alter the pH by more than 0.2 increments daily. Establish a stable pH which your koi can live with, somewhere between 6.8 and 8.2. Quite often, regular water changes will stabilize pH, however some parts of the country have poorly buffered tap water and you may need to add some type of buffer to the pond.

Conclusion
We have seen that creating a stable balanced pond is a lot more than just producing good numbers. We have learned that to take care of the fish we must take care of the Living Water.
Good "Living Water Quality" is determined by the health of the microorganisms in a dynamic equilibrium. The stability of the pond, chemically and physically, determines the health of these microorganisms. Water stability is an end product of planning and proper design. Water stability takes time and patience. It requires staying within limits. Maintaining stability requires a filter system that can be cleaned without disrupting the pond. Long term stability means developing a maintenance program that is not disruptive. Each pond will acquire it's own unique state of balance. Be flexible. Observe your pond water conditions and your fish every day. You are aqua-culturists. You must learn to culture stable Living Water. The Living Water will take care of your fish.